Non-staining liquid lubricant



11 Claims Int. Cl. (310m 1/40 ABSTRACT OF THE DISCLOSURE A liquidmineral oil-free lubricating composition that is particularly suited foruse in the drilling of earth formations with a diamond coring bit, andwhich is superior to previous lubricants for this purpose in that itdoes not cause staining of the earth cores, comprises from 3 to 25weight percent of a salt of an alkylated aromatic sulfonic acid, from 3to 25 weight percent of a solubilizing agent, from 1 to 10 weightpercent of a rust inhibitor and from 40 to 93 weight percent of water.The composition can be added to the circulating stream of water used inthe drilling operation at the rate of 1 volume of lubricant per 200 to1000 parts of the circulating water.

This application is a continuation-in-part of application Ser. No.476,664, filed Aug. 2, 1965, now abandoned.

The present invention relates to a water-based liquid lubricatingcomposition. In general, it concerns a nonstaining liquid lubricatingcomposition particularly useful for diamond core drilling. Inparticular, it concerns a nonstaining liquid lubricating compositioncontaining an alkyl aryl metal organic sulfonate as a lubricity agentand the use of such a composition in the drilling of earth formationswith a diamond drill coring bit.

In many industrial lubricating applications, staining of surfaces comingin contact with the lubricant is a problem. For example, in the Canadianmining industry where exploratory drilling is carried out using diamondcore drilling apparatus to search for ore bodies, lubrication of theapparatus with conventional lubricants generally results in staining ofthe cores of rock and ore that are bored out by the diamond drill bit.Diamond bit coring is conventionally conducted by rotating a reamer anddiamond drill bit on a string of drill pipe in a bore hole. It is therotary action of the diamonds grinding against the rock and the weightof the drill rod assembly bearing down on the rock at the bottom of thehole which causes the assembly to penetrate into the rock. Thedoughnut-shaped diamond drill bit grinds out a smooth-surfacedcylindrical rock core (about one inch in diameter) which is pushed upinto the inner core tube. The drill pipe is removed from the hole afterevery 10 to 20 feet of drilling to recover the rock cores. Recently anew technique has been perfected whereby a line equipped with a specialclamp to fasten onto the core samples is lowered down through the drillpipe and the core samples are recovered without the necessity of raisingand uncoupling the many feet of drill pipe. This new technique makes itespecially mandatory that a non-staining lubricant be used.

In diamond core drilling, water, usually called fresh sludge water, ispumped down the drill pipe to flush the debris formed around the diamondbit back up through the annulus between the drill pipe and the walls ofthe hole and to serve as a coolant for the cutting diamonds. It alsoprovides some lubrication to the rotating drill line. A string of drillrods or pipe which are not properly lubricated will cause the inherentvibrations common to a long rod or pipe to become severe. This conditioncreates impact forces that are transmitted to the diamond bit with nitedStates Patent 3,425,940 Patented F ch. 4, 1969 damaging effects. Therecovery of the cores is also adversely affected under such conditions,since the vibration breaks the cores into smaller pieces. The rate ofpenetration of the bit is greatly reduced and will cease if thevibrations become too severe.

For some years a special grease has been marketed to coat the outside ofthe drill pipe to provide extra lubrication and to seal the hole wherecaving conditions are encountered due to fragile rock. The use of greasedid permit greater drilling speed and provided some rust protection tothe rods under these conditions. The use of a grease applied to thedrilling apparatus so as to lubricate only the external surface of drillrods or pipe will result innon-staining of the cores, but at the sametime neither the internal surface of the core barrel or tube nor thediamond drill bit is lubricated with the grease; thus, there is nointernal lubrication and the life of the bit is decreased. In a likemanner, when water alone is used as a lubricant, no core stainingoccurs. However, lubrication, both external and internal, is very poor,and in many instances vibrations are so great that drilling must cease.

More recently it was found that a soluble oil, e.g., an emulsifiable oilcomprising a major proportion of a mineral lubricating oil and a minorproportion of one or more anionic emulsifiers, when metered into thefresh sludge water, markedly increased the cutting speed and bit life.

In most instances however, use of the soluble oils caused deposition ofa tenacious insoluble film on the surface of the rock cores. This filmprevented the geologist from identifying, by visual inspection, the oresand rocks contained in the core. An analysis of the deposit showed thatit was composed of 50% of a black magnetic iron oxide (of such finecrystalline structure as to make identification by X-ray Diffractiontechniques difiicult), and 50% of a resinous organic binder. The ironoxide appeared to have been ground into the pores of the rock core.

In accordance with the present invention, there is provided a liquidlubricant which does not stain and which possesses very good lubricityproperties. This lubricant is employed in the same manner as with theprior practice when using the so-called soluble oils, i.e., it is alsometered into the fresh sludge water used in the diamond drillingoperation. Usually about 1 part by volume of the composition of thepresent invention will be employed with about 200 to 1000 parts, andpreferably 200 to 400 parts, by volume of water (e.g., fresh sludgewater).

The composition of the present invention comprises a metal salt of analkyl aryl su-lfonie acid, as the lubricity additive; a n0n-stainingsolubilizing agent, which solubilizes the sulfonate in water; anon-staining rust inhibitor; and water, as a carrier.

The alkyl aryl metal sulfonate employed as the lubricity additive of thepresent invention is well known to the art as a surface active agent.The metal portion of the sulfonate can be sodium, potassium, lithium orammonium, preferably sodium. The alkyl portion of the sulfonate containsabout 6 to 18 carbon atoms, preferably 10 to 14 carbon atoms, e. g.,dodecyl. The aryl portion of the sulfonate can be benzene, diphenyl, ornaphthalene. Benzene is particularly preferred. Examples of sulfonatessuitable for use in the present invention include, but are not limitedto, sodium dodecyl benzene sulfonate, potassium nonylbenzene sulfouate,ammonium octyl benzene sulfonate, sodium cetyl naphthalene sulfonate,lithium decyl benzene sulfonate, etc. The above-described sulfonates areanionic surface active agents and their methods of preparation are wellknown to the art. Such sulfonates are readily available for exampleunder the trade names Deltamin AB 80, Sorapon SX Slurry, etc.

The solubilizing agent employed in the present invention must bewater-soluble and must also be non-staining. One such solubilizer isTriton X-l02, which is isooctylphenyl polychtoxy ethanol, i.e., thereaction product of isooctylphenol and ethylene oxide. This reactionproduct has an average of 12 to 13 oxyethylene units. Anothernon-limiting example of a suitable solubilizer is urea.

P-articula-rly effective solubilizers are the alkyl phenyl polyalkoxyalkanols, which are obtained by reacting to 15 molar proportions of a Cto C alkylene oxide with one molar proportion of an alkyl phenol havinga C to C alkyl group, e.g., the reaction product of 6 moles of propyleneoxide with one mole of dodecyl phenol, the reaction product of a mixtureof 5 moles of ethylene oxide and 5 moles of propylene oxide with onemole of nonyl phenol, and the reaction product of 8 to 10 moles ofethylene oxide with one mole of isooctyl phenol. These are includedwithin a broader class of solubilizers having the formulas:

where R is a C to C hydrocarbon group, A is oxygen or sulfur and x is 8to 20, which would include, in addition to the alkyl phenol derivativesdescribed above, the alkyl thiophenol derivatives and the higher alcoholethers and higher mercapto ethers of the alkylene oxides or thepolyglycols.

Still other suitable solubilizers include the sodium, potassium, orammonium salts of toluene sulfonic acid or of xylene sulfonic acid.Another solubilizer comprises a mixture of 1 to 10 parts by weight ofthe tetrasodium salt of ethylene diamine tet-racetic acid with 1 part ofthe sodium salt of N, N-di-(Z-hydroxyethyl) gylcine and/or 1 part of thesodium salt of hydroxyethyl ethylene diamine triacetic acid.

The composition of the present invention employs a non-stainingwater-soluble rust inhibitor to provide rust protection for thecontainer during shipment and for the drill rods during use. Suitablerust inhibitors include, but are not limited to, sodium benzoate, sodiumnitrite, triethanolamine, sodium borate, sodium dichromate, thiourea,etc. Sodium benzoate is preferred.

In general, the above-described three components of the composition ofthe present invention will be used with a Water carrier in the followinggeneral proportions:

Weight percent The above weight percentages are based upon 100 percentactive ingredient. Sulfonates suitable for use in the present inventionare often supplied in concentrate form. For example, Sorapon SX Slurryis a concentrate of about 45% by weight of sodium dodecyl benzenesulfonate in 55 weight percentage water. The dodecyl group is derived byalkylating benzene with tetrapropylene.

Various other ingredients may be added to the compositions of thepresent invention. For example, antifoamants such as silicone fluid DC200 (350 centistokes), dyes such as Disuphine Blue VN 150, and otherconventional additives may be employed for their known effects.

When the liquid lubricating composition is diluted with water in theproportion of 1 volume of the composition and 200 to 1,000 volumes ofwater, there will be obtained a circulating fluid which will consistessentially of about 200 to 1,000 parts by weight of water, from 0.03 to0.25 part by weight of the sulfonate, from 0.03 to 0.25 part by Weightof the solubilizing agent, and from about 0.01 to 0.1 part by Weight ofthe rust inhibitor.

The present invention will be further described by reference to thefollowing examples.

Example 1 A non-staining lubricant composition of the present inventionwas prepared by simple mixing of 20 weight percent Sorapon SX Slurry, 10weight percent Triton X-102, 5 weight percent sodium benzoate and 65weight per-cent water. To this was added about 0.002 weight percentdisulphine blue dye VN 150 for identification purposes. The resultingviscous blue liquid composition had a specific gravity of 1.06 at 60 F.,a solids content (by evaporation) of 24 weight percent and a viscosityat F. of about 360 SUS. It had good low-temperature stability, therebeing no separation of components after several hours storage at 0 F.

This composition was found to be eminently suitable for use in diamonddrilling operations by metering about 1 gallon of the composition intoabout 400 gallons of water. For example, when Water is circulatingthrough the drill pipe at 1,200 gallons per hour, 3 gallons per hour ofthe described composition is metered into the circulating water.

In a typical operation a rock formation in an exploration hole at adepth between 6,600 and 10,000 feet below the surface Was cored with adiamond bit, using circulating water to which the above composition hadbeen added in the proportion of 1 gallon per 400 gallons of water. Therewas essentially no staining of the recovered cores and lubrication ofthe drill pipe was good as evidenced by lack of vibration.

Example 2 A lubricant composition is prepared by simple mixing of 13weight percent of ammonium isooctyl benzene sulfonate, 14 weight percentof nonylphenyl polypropoxy propanol, 4 weight percent oftriethanolamine, and 69 weight percent of water. The isooctyl benzenesulfonate is derived from benzene that has been alkylated withdiisobutylene. The nonylphenyl polypropoxy propanol is the reactionproduct of mixed nonylphenols with 8 to 9 molar proportions of propyleneoxide. The mixed nonylphenols consist of 76 Weight percent ofmonononylphenol and 24 weight per-cent of dinonylphenol resulting fromalkylation of phenol with tripropylene.

The lubricant composition thus prepared is mixed with Water in theproportion of 1 part of lubricant to about 500 parts of water toconstitute the circulating and lubricating fluid for coring a rockformation in -a bore hole in the earths surface using a diamond coringbit.

While the lubricating composition of the present invention has beendescribed primarily as a non-staining lubricant for diamond coredrilling operations, the composition also finds utility in other liquidlubricating ap plications. For example, it can be used without furtherdilution as a way lubricant, i.e., as a fabrication lubricant applied tothe cooling beds for the lubrication of hot steel bars as they slidedown the bed and onto the ways. In this respect it is superior to themore expensive gr-aphited lubricants and acidless tallows commonlyemployed as way lubricants. The composition can also be employed as ametal cutting fluid, or as a roll oil in the fabrication of metalsheets. Colloidal graphite may also be added to this composition forspecific applications.

It is to be understood that the examples presented herein are intendedto be merely illustrative of the invention and not as limiting it in anymanner; nor is the invention to be limited by any theory regarding itsoperability. The scope of the invention is to be determined by theappended claims.

What is claimed is:

1. A non-staining liquid mineral-oil-free lubricating compositionconsisting essentially of from 3 to 25 Weight percent of a sulfonatesalt selected from the group consisting of the sodium, potassium,lithium, and ammonium salts of alkylated aromatic sulfonic acids whereinthe alkyl groups have about 6 to 18 carbon atoms, from 3 to 25 weightpercent of a Solubilizing agent, from 1 to 10 weight percent of a rustinhibitor and from 40 to 93 weight percent of water, said solubilizingagent being selected from the group consisting of urea, 21 sodium, po-

tassium, or ammonium salt of toluene sulfonic acid, a sodium, potassium,or ammonium salt of xylene sulfonic acid, a phenyl polyalkoxy alkanolobtained by reaction of 5 to 15 moles of a C to C alkylene oxide withone mole of an alkyl phenol having a C to C alkyl group, a mixture ofethylene diamine tetrasodium tetra acetate and sodium salt of N,N-di-(Z-hydroxyethyl) glycine, and a mixture of ethylene diaminetetrasodium tetra acetate and sodium salt of hydroxyethyl ethylenediamine triacetic acid, said rust inhibitor being a water-soluble rustinhibitor selected from the group consisting of sodium benzoate, sodiumnitrite, triethanol amine, sodium borate, sodium dichromate, andthiourea.

2. Composition as defined by claim 1 wherein said alkyl groups rangefrom about to 14 carbon atoms.

3. Composition as defined by claim 1 wherein said sulfonate is sodiumdodecyl benzene sulfonate.

4. Composition as defined by claim 1 wherein said solubilizing agent isthe product of alkoxylation of a C to C alkyl phenol with from 5 tomoles of a C to C alkylene oxide.

5. Composition as defined by claim 1 wherein said solubilizing agent isisooctyl phenyl polyethoxy ethanol having 12 to 13 oxyethylene units.

6. Composition as defined by claim 1 wherein said rust inhibitor issodium benzoate.

7. In the drilling of a well bore in the earth wherein a core sample isobtained by a coring device at the lower end of a string of drill pipeand wherein said drill pipe and said coring device are lubricated bycirculation of Water through the drill pipe and the coring device, theimprovement which comprises adding to said circulating water one volume,per 200 to 1000 volumes of said water, of the liquid lubricatingcomposition defined by claim 1.

8. A circulating fluid for the lubrication of a string of drill pipe andan earth coring device suspended therefrom in a well bore which consistsessentially of a mixture of from 200 to 400 volumes of water and 1volume of the lubricant composition defined by claim 1.

9. Circulating fluid as defined by claim 8 wherein said lubricantcomposition consists essentially of: (1) about weight percent of aslurry of 45 weight percent of sodium dodecyl benzene sulfonate, about55 weight percent of water; (2) about 10 Weight percent of isooctylphenyl polyethoxy ethanol having from 12 to 13 oxyethylene units; (3)about 5 weight percent sodium benzo-ate; and (4) about 65 weight percentof water.

10. A mineral oil-free circulating fluid for the lubrication of a stringof drill pipe and an earth coring device suspended therefrom in a wellbore which consists essentially of about 200 to 1000 parts by weight ofwater, from about 0.03 to 0.2 part of a sultonate salt selected from thegroup consisting of the sodium, potassium, lithium and ammonium salts ofalkylated aromatic sultonic acids wherein the alkyl groups have fromabout 6 to 18 carbon atoms, from about 0.03 to 0.2 part of asolubilizing agent and from 0.01 to 0.1 part of a rust inhibitor, saidsolubilizing agent being selected from the group consisting of urea, asodium, potassium, or ammonium salt of toluene s-ulfonic acid, a sodium,p0- tassium, or ammonium salt of xylene sulfonic acid, a phenylpolyalkoxy alkanol obtained by reaction of 5 to 15 moles of a C to Calkylene oxide with one mole of an alkyl phenol having a C to C alkylgroup, a mixture of ethylene diamine tetrasodium tetra acetate andsodium salt of N, N-di-(Z-hydroxyethyl) glycine, and a mixture ofethylene diamine tetrasodium tetra acetate and sodium salt ofhydroxyethyl ethylene diamine triacetic acid, said rust inhibitor beinga water-soluble rust inhibitor selected from the group consisting ofsodium benzoate, sodium nitrite, triethanol amine, sodium borate, sodiumdichromate, and thiourea.

11. Fluid as defined by claim 10 wherein said solublizing agent is theproduct of alkoxylation of a C to C alkyl phenol with from 5 to 15 molesof a C to C alkylene oxide.

References Cited UNITED STATES PATENTS 2,568,992 9/1951 Doscher 252-2,610,151 9/1952 Putman et a1. 252-333 2,617,296 11/1952 W'isenbaker252-85 X 2,832,736 4/1958 Jezl 252-333 3,112,799 12/1963 GalluS 252-85 X3,150,085 9/1964 Mallory 252-85 3,308,068 3/1967 Jones 252-85 X2,796,429 6/1957 Kreps et a1. 252-161 X 3,282,843 11/1966 Alburger252-495 X OTHER REFERENCES Rogers, Composition and Properties of OilWell Drill ing Fluids, Third Edition, pub. 1963 by Gulf Pub. Co. ofHouston, Texas, pp. -121.

HERBERT B. GUYNN, Primary Examiner.

US. Cl. X.R.

